Treatment of hydrocarbon oils



1 J. G. ALTHER 8 TREATMENT OF 'HYDROOARBON OILS Original Filed Feb. 16. 1951 INVENTCR JOSEPH c. ALTHER ATTORNE Patented July 6, 1937 V TREATMENT OF HYDROCARBON OILS Joseph G. Alther, Chicago, Ill., assignor, by mesne assignments, to Universal Oil Products Company, Chicago, 111., a corporation of Delaware 7 Application February 16, 1931, Serial No. 516,016 Renewed February 12, 1935 v 5 Claims.

This invention relates to the treatment of hydrocarbon oils, and refers more particularly to the treatment of heavy liquid residuals produced as by-products of cracking operations.

More particularly the invention contemplates the provision of a process whereby such heavy liquid. residuals may be treated under relatively mild conversion conditions to render them less viscous and more adaptable to use as liquid fuel.

* In the treatment under elevated temperatures and pressures of hydrocarbon mixtures to produce substantial yields of low boiling fractions suitable for use as motorfuel there are produced as by-products fixed gases and vaporstoo light for gasoline on the one hand and residual products heavier than'gasoline on the other, and it is with the improvement of 'these latterfractions that the present invention is concerned.

Such heavy liquid fractions will vary in consistency from liquids of relatively low viscosityat-or-- dinary atmospheric temperatures to liquids of increasing viscosity and finally to semi-solid or solid residues as'the severity of treating conditions is increased. 7

In many processes suitable fractionatin'gde vices separate the residual liquids into fractions of intermediateboiling point range amenable to further conversion andheavy tarry or pitchy residues which it is difficult to crack further without the concurrent amounts of heavy carbonaceous solids resembling coke, these coke deposits causing'difiiculty during the retreatment in producing overheating of tubes and rendering the fluid residues containing the particles in suspension: unfit for use as fuel oil in atomizing burners.

The present invention contemplates the processing of the heavy or pitch-like fractions from craclL'ng processes insuch' a manner as to produce oils of maximum fluidity with a minimum production of carbonaceous particles and a further minimum production oflsupplementaryyields of hydrocarbons of gasoline boiling point range.

In one specific embodiment theinvention comprises passing a cracked residuum through a heating element along with refluxcondensate produced at a later stage of the process, discharging the heated products into'an enlarged vaporizing or reaction vessel, passing the total products from the reaction zone either directly or a portion thereof through a:cooler to a relatively low pressure vaporizing zone, passingthe' vapors from the vaporizing zone tosuitable fractionating equipment, vapors from which" are cooled, condensed and collected, passing bottomproduction of undesirable liquids from the fractionating stage either to' the heating element for further treatment withthe charging oil, or partly-tostoragemixed withv theliquids separated in the vaporizing zone and a certain portion of the cooled products from the reaction zone. 7

To assist in describing in essential detail an operation comprised within the scope of the invention, the attached diagrammatic drawing, has been provided which shows ina conventional manner a side elevation of an arrangement of elements which may be used...

Cracked residue from any source, for example, from the intermediate vaporizing elements I of cracking processes, may be taken by pump 3 from line i containing valve 2 and discharged intoline= 4 containing valve 5, this line leading to heating element fixdisposed in furnace l. Prior'to entering the heating element the charging oil may he mixed with certain portions of reflux condensates fromline .29, as will be later more fullydescribedz,

by the heating are allowed to progress to aydesireddegree. Chamber I0 is preferably well in sulated to conserve heat necessary for -the'endo-: thermic reactionsinvolved and typifies any 'ar-' rangement of :such chambers in series or parallel. .The temperatures employed atthe outlet ofthe heating-element vary widely with;the:stocks being treated and are commonly within the'range of 800.to 950 F., temperatures inv the neighbor-, hood of 900 F. being'not uncommon. The pressures employed during passage throughtheelement and the succeeding zones may be'superatmospheric to as high as 300-pounds persquare' inch or higher; the good results have been ob-" tained when operating at pressures only moderately superatmospheric, such as 100 poundsper. square inch. I H 4 v It is characteristic of the present invention that relati velymild conditions of temperature and pressureare'employed the operation being: adjusted 'inspecific cases'to permit maximum-Y reduction in viscosity with minimized productionj The apparatus may.

of coke and light fractions. be designed in certainv casesv to produce-a rela-. tively. short heating. period at the temperatures employed, wthis heating period being governed by the tendency of the charging oilto deposit coke. particles interfering with the operation of the process. The total products of the reactions from'ueaction' chamber I0 are preferably discharged through line I I containing valve [2 Heated materials: leave heating element 6 through line 8 containingvalve 9,J'and pass into: enlarged chamber 'l,0,'in which reactions initiated:

FFICE I through cooler l3 which may be any device for lowering the temperature of the discharged products to a point at which the conversion reactions are halted.

5 In some cases cooling may not be necessary and then the discharged products mayv be passed through line H containing valve [2' where they pass into and through line IE to vaporizing chamber [8, which is preferably held under pressures substantially lower than those employed in the conversion zone. found that the products issuing from reaction chamber l0 and passing through cooler I3 are of a quality and consistency suitable for commercial use as fuel oil, and in such cases line l4 containing valve 15 is provided to permit their egress to suitable storage either alone or mixed with certain portions of liquids later produced in the process. Evaporating chamber I8 is of a type suitable for the production of vapors containing substantially all of the hydrocarbons of motor fuel boiling point range and separation of heavy liquids of a degree of consistency approximately equivalent to that desired, the vapors therefrom passing through line 2! containing valve 22 to fractionator 23 and the liquids through line H! containing valves 20 and 48 leading to suitable storage.

In fractionator 23 accurate separation of h drocarbons boiling within the motor fuel range is effected, their physical quality being controlled by the liquids recirculated from line 46. These vapors pass through line 33 containing valve 34 to condenser 35 which condenses gasoline. fractions, the cooled products passing through line 35 35 containing valve 31 to receiver 38 from whence excess accumulations of gases may be released to line 39 containing valve 40 and gasoline fractions removed through line 4| containing valve 42. To assist in accurately controlling the boiling point 0 range of the gasoline vapors line 43, containing valve 44, is providedleadlng to pump 45, which discharges a suitable portion of the gasoline through line 46 containing valve 41 to the top of fractionator 23 as already indicated. Reflux con- 45 densates from fractionator 23 pass through line 24 containing valve 25 either for reconversion along with charging stock or for blending with liquids produced either in reaction chamber 10 or vaporizing chamber l8. When it is desirable to utilize a portion or all of them for reconversion along with the charging stock they are withdrawn through line 26 containing valve 21 leading to pump 28 which discharges into line 29 containing valve 30 leading to line 4 and the heating element as previously mentioned. The portions allowed to discharge through line 3| containing valve 32 blend with the heavy liquids coming from chamber I!) through line I 4 and vaporizing chamber I8 through line 19, respectively, the blending resulting in further substantial reduction in viscosity due to the so-called "cutting action of the intermediate oils.

It will be evident from the preceding description that the process of the invention may be operated to effectively treat and render more fluid cracked residue produced in a variety of ways and possessing a wide range of chemical and physical characteristics. The example of operation given, therefore, while typical of the process, is illustrative merely of many modes of operation. Certain charging stocks require the application of extremely mild conditions and others may require more severe conditions resulting in the higher 7 production of gasoline and the ntw sity for em- In some instances it may be cient return of reflux condensates to insure proper viscosity reduction.

As a particular example of the results obtainable by one operation of the process of the invention, a heavy residuum from the cracking operation was utilized as charging stock, this residuum having a viscosity of 97 seconds at 210 F. when tested in the Saybolt universal viscosimeter. After being treated at approximately 100 pounds pressure per square inch and temperature at the 10 outlet of the heating element of 900 F. the viscosity of the residuum was found to be reduced to 50 seconds at 210 F. with a yield of approximately 88% of the charging oil as fuel oil, approximately 4% of gasoline and 8% loss as fixed 15 gases.

I claim as my invention:

1. A process of substantially decreasing the viscosity of a hydrocarbon residue resulting from the cracking of hydrocarbon oil, which comprises 20 subjecting said residue to heat in a heating zone, discharging said heated residue into an enlarged reaction zone, maintaining superatmospheric pressure in the heating zone and the enlarged reaction zone, removing all of the products of 25 reaction from said enlarged reaction zone, directing a regulated portion thereof to an enlarged zone of reduced pressure while simultaneously subjecting another portion thereof to cooling action, separating vapors from non-vaporous residue 30 in said reduced pressure zone, commingling the non-vaporous residue withdrawn from said reduced pressure zone with that portion of the reaction products which were subjected to cooling and recovering the resultant mixture as a product of 35 the process, separately removing vapors from said reduced pressure zone and subjecting same to condensation.

2. A process of substantially decreasing the viscosity of a hydrocarbon residue resulting from 40 the cracking of hydrocarbon oil, which comprises subjecting said residue to heat in a heating zone,

discharging said heated residue into an enlarged reaction zone, maintaining superatmospheric pressure in the heating zone and the enlarged 45 reaction zone, removing all of the products of reaction from said enlarged reaction zone, directing a regulated portion thereof to an enlarged zone of reduced pressure while simultaneously subjecting another portion thereof to cooling ac- 50 tion, separating vapors from non-vaporous residue in said-reduced pressure zone, commingling the non-vaporous residue withdrawn from said reduced pressure zone with that portion of the reaction products which were subjected to cooling and 55 recovering the resultant mixture as a product of the process, separately removing vapors from said reduced pressure zone and subjecting same to fractionation to separate the heavier fractions thereof as reflux condensate, returning regulated 60 portions of said reflux condensate to the heating zonefor retreatment.

3. A process of substantially decreasing the viscosity of a hydrocarbon residue resulting from the cracking of hydrocarbon oil, which comprises 65 subjecting said residue to heat in a heating zone, discharging said heated residue into an enlarged reaction zone, maintaining superatmospheric pressure in the heating zone and the enlarged reaction zone, removing all of the products of reac- 70 tion from said enlarged reaction zone, directing a regulated portion thereof to an enlarged zone of reduced pressure while simultaneously subjecting another portion thereofto cooling action, separating vapors from non-vaporous residue in said 7 reduced pressure zone, commingling the nonvaporous residue Withdrawn from said reduced pressure zone with that portion of the reaction products which were subjected to cooling, separately removing vapors from said reduced pressure zone and subjecting same to fractionation to separate the heavier fractions thereof as reflux condensate, returning regulated portions of said reflux condensate to the heating zone for retreatment and mixing another portion of said reflux condensate with the mixture of residue withdrawn from the reduced pressure zone and the cooled reaction products and recovering the resultant mixture as a product of the process.

4. A process for substantially reducing the viscosity of a hydrocarbon residue, which comprises subjecting the residue to viscosity reducing conditions of temperature and pressure in a conversion zone, removing all of the products of reaction from said zone, directing a regulated portion thereof to an enlarged zone While simultaneously subjecting another portion thereof to cooling action, separating vapors from non-vaporous residue in said enlarged zone, cornmingling the nonvaporous residue from said enlarged zone with that portion of the reaction products which were subjected to cooling, separately removing vapors from said enlarged zone and subjecting the same to fractionation to separate heavier fractions thereof as reflux condensate, returning regulated portions of said reflux condensate to the conversion zone for retreatment, and mixing another portion of said reflux condensate with the mixture of residue from said enlarged zone and the cooled reaction products.

5. A process of substantially decreasing the viscosity of a hydrocarbon residue which comprises subjecting said residue to heat in a heating zone, discharging said heated residue into an enlarged reaction zone, maintaining superatmospheric pressure in the heating zone and the enlarged reaction zone, removing all of the products of reaction from said enlarged reaction zone, directing a regulated portion thereof to an enlarged zone of reduced pressure While simultaneously subjecting another portion thereof to cooling action, separating vapors from nonvaporous residue in said reduced pressure zone, commingling the non-vaporous residue withdrawn from said reduced pressure zone with that portion of the reaction products which were subjected to cooling, separately removing vapors from said reduced pressure zone and subjecting same to fractionation to separate the heavier fractions thereof as reflux condensate, returning regulated portions of said reflux condensate to the heating zone for retreatment and mixing another portion of said reflux condensate with the-mixture of residue withdrawn from the reduced pressure zone and the cooled reaction product.

JOSEPH G. ,ALTI-IER. 

